Dwayne used 2 gallons of paint to cover 750 square feet and 5 gallons of paint to cover 1,875 square feet if the area covered y varies directly with the amount of paint used x then how many gallons of paint will be used to cover 2,625 square feet

Find the directions in which the function increases and decreases most rapidly at upper p 0p0. then find the derivatives of the function in these directions. f(x,y)equals=x squared plus xy plus y squaredx2+xy+y2, upper p 0p0left parenthesis 1 comma negative 4 right parenthesis